Improvement in blasting rock



G. C. BUNYSEN.

Blasting Rocks.

No.. 47,925.' Patented May 30, 1865.

witnesses; Y Inventor".

anca/6 Y Qi@ UNITED STATES PATENT OFFICE.

GEORGE BUNSEN, OFBELLEVILLE, ILLINOIS.

IMPROVEMENT IN BLASTING ROCK.

Specification forming part of Letters Patent No. 47,925, dated May 30, 1865.

To @ZZ whom it may concern,.-

Be it known that I, GEORGEl C. BUNsEN, of Belleville, in the county ot' St. Clair and State o1" Illinois, have invented certain new and useful Improvements in Blasting Rock; and I do hereby declare that the following is a full, clear, and exact description ofthe construction au d operation of the same, reference being` had to the accompanying drawings, in whiclr Figure l represents a perspective view oi the device I employ in blasting. Figs. 2 and 3 .represent modilied constructions ot' said device.

To enable. others skilled in the art to make and use my invention, l will proceed to describe its construction and operation.

It is a well-known fact that in firing a charge ofpowder which is contained in a closed space-such as the barrel of a tire-arm or t-he cavity ot' a blast-drill-the explosive power ot' the powder is vastly increased if an airspace is lel't between the powder and the projectile or rock to be acted -upon,owing to the greater heat produced by the oxygen ot' the air when the powder is burned. This is the case to such an extent-that when in an ordinary powder charge an air-space is left between the charge and the projectile-or, in

other words, when the projectile is not firmly ranuucd down on the powder-the charge, when tired, is sure to burst the tire-arm, from the fact that the expansive power of t-he burningl powder, when mixed with air, be comes so great and its action is so instantaneous that the projectilehas no time to escape from the gun-barrel, and therefore the latter bursts. By the application of this prineipleI have succeeded in inventing an extremely simple device, by which I ani enabled not only to use a smaller quantity of powder than has been used heretofore for producing a certain eiiect in blast-ing, but by which also the labor ot' plugging the drill-hole is materially lesscned.

I employ a hollow cylinder, d, whose frontend is closed by a plate, a, with the exception of a small hole, b, for entering the fuse or miners pin. To the rear of the cylinder I secure a rod or support, c, whose end extends to the bottom of the drill. The cylinder d is filled with.blasting-powder, and, when inserted into the blast-drill, an air-space is eft therein, equal to the lengthof the support c, between the powder and the bottom ot' the drill.

The device, when inserted into the drill, may either be secured therein by a small plug, or, it' it lits the hole tightly, such a plug even may be dispened with, and," when the charge is tired, the explosive power ofthe powder acts directly to the rear, and, owing to t-he admixture ot' atmospheric air, is so instantaneous as to blast the rock wit-hout dis charging the cylinder or capsule from the blast-drill.

I provide the cylinder d, in front of the hole b, with a small scoop, E, which is lilled with powder, and is in connection with the train by which the charge is lired.

This device may be inodiiied in its construction, and the cylinder (l may be entirely dispensed with, leaving only a disk or plate, a, which fills the drill, and to which a support, c, is secured, which extends to the bottom of the drill, and the powder is held in its place by a plate, a, represented at Fig. 2.

My device may further be modified by dispensing` wit-h the support cand by using a cylinder only. In the latter case the disk a of the cylinder should be provided with a rim or 1lange,f, on which a yielding materialsuch as lead, india-rubber, or other packing, g-can be fastened, and the disk a should be of sut'eient strength that it can be driven into the drill-hole acertain distance and leave an airspace behind the cylinder and between it and the rock. This latter modilieatiou also renders the employment ot' a plug supertluous, as the disk a. and its packing can be driven into the hole perfectly air and powder tight. The lat-ter operation maybe morcperl'ectly effected it' a short space of the hole is made slightly conical. The device in its last-named modification is represented at Fig. 3.

Having thus fully described the nature of my invent-ion, what I claim herein as new, and desire to secure by Letters Iatent, is-

The application i'or blasting purposes of a disk, a, when used either with a cylinder, d, or support c, or in combination with both cylinder and support, substantially in the man ner and for the purposes specitied.

. GEO. tv. BUNSE. VitneSseS:

G. ABERER,

JAMES H. Wnwnn. 

